/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
*/

package org.apache.kylin.measure.bitmap;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Created by sunyerui on 15/12/22.
 */
public class BitmapDistinctCountAggFunc {

  private static final Logger logger = LoggerFactory.getLogger(BitmapDistinctCountAggFunc.class);

  public static BitmapCounter init() {
    return null;
  }

  public static BitmapCounter add(BitmapCounter counter, Object v) {
      BitmapCounter c = (BitmapCounter) v;
      if (counter == null) {
        return new BitmapCounter(c);
      } else {
        counter.merge(c);
        return counter;
      }
  }

  public static BitmapCounter merge(BitmapCounter counter0, Object counter1) {
      return add(counter0, counter1);
  }

  public static long result(BitmapCounter counter) {
      return counter == null ? 0L : counter.getCount();
  }
}
